Build It With Phoenix by Geoffrey Lessel
Build It With Phoenix
Build It With Phoenix by Geoffrey Lessel is a hands-on Elixir and Phoenix development course focused on building a complete real-time chat application from scratch using modern Phoenix technologies like LiveView, Presence, Channels, Ecto, PubSub, and Postgres.
Instead of focusing on disconnected lessons, this course walks developers through the complete process of building a real-time chat platform using Elixir and Phoenix technologies like LiveView, Presence, Channels, PubSub, Ecto, and PostgreSQL.
The project structure feels much closer to a real-world application inspired by platforms like Slack or Discord rather than a basic tutorial app.
One of the strongest aspects of the course is its practical development workflow. Geoffrey Lessel doesn’t simply show the “perfect” implementation from the beginning.
The course demonstrates how applications evolve through debugging, refactoring, architecture improvements, and changing requirements, which is often the part missing from most Phoenix tutorials.
What You’ll Learn
Throughout the course, you’ll build a complete real-time application while learning how modern Phoenix systems actually work behind the scenes.
Topics covered include:
- Phoenix LiveView fundamentals
- Real-time messaging systems
- WebSocket communication
- User presence tracking
- Authentication workflows
- Phoenix Channels and PubSub
- Database persistence with Ecto
- PostgreSQL integration
- Real-time UI updates
- Scalable application architecture
- Refactoring and debugging workflows
The course is especially useful for developers who want hands-on experience building interactive real-time applications without relying heavily on frontend JavaScript frameworks.
Technologies Covered
The training uses a modern Phoenix stack and focuses on tools commonly used in production Elixir applications.
Elixir 1.15
Learn functional programming concepts while building scalable backend systems with Elixir.
Phoenix 1.7
Build high-performance web applications using one of the fastest modern backend frameworks.
Phoenix LiveView
Create dynamic real-time interfaces with server-rendered updates instead of complex frontend SPA frameworks.
Phoenix Presence and Channels
Implement connected-user tracking, typing indicators, and real-time communication systems.
Ecto and PostgreSQL
Manage database persistence, queries, validations, and relational workflows for chat data and user accounts.
Tailwind CSS
Style the interface using utility-first frontend workflows integrated directly into Phoenix.
Build It With Phoenix Course Breakdown
The course is structured around progressively building a fully functional chat application.
Phase 1 — Building the Chat System
The first section focuses on creating the core real-time messaging experience using LiveView and Phoenix PubSub.
You’ll learn how to:
- create chat rooms
- broadcast messages in real time
- manage anonymous users
- synchronize multiple connected clients
- structure LiveView components properly
By the end of this phase, you’ll already have a working multi-user chat application.
Phase 2 — Presence and Real-Time Features
This section introduces advanced interactive features using Phoenix Presence and Channels.
Topics include:
- connected-user tracking
- join and leave notifications
- typing indicators
- real-time synchronization
- user activity systems
These lessons help demonstrate why Phoenix is particularly powerful for real-time applications.
Phase 3 — Authentication and Persistence
The final section focuses on transforming the application into a more complete production-style system.
You’ll implement:
- user authentication
- persistent chat history
- Ecto schemas and changesets
- Postgres integration
- validation systems
- authenticated messaging
This phase helps bridge the gap between demo applications and real-world backend architecture.
What Makes This Course Valuable
Many Phoenix courses focus heavily on syntax or isolated framework features.
Build It With Phoenix stands out because it focuses on the development lifecycle of a real application. Instead of only teaching “how Phoenix works,” the course demonstrates how developers actually build, debug, improve, and maintain real-time systems over time.
That practical approach makes the material far more useful for developers who want production-oriented experience instead of theoretical examples.
The course also provides a strong introduction to:
- LiveView architecture
- state synchronization
- scalable messaging systems
- real-time UX patterns
- backend-focused full-stack development
Who This Course Is For
This course is best suited for:
- Elixir developers
- backend engineers
- Phoenix beginners
- full-stack developers
- developers interested in real-time systems
- programmers transitioning into Phoenix development
Previous programming experience is recommended, though deep Phoenix knowledge is not required to start.
About Geoffrey Lessel
Geoffrey Lessel is a software engineer, educator, conference speaker, and the author of Phoenix in Action. He has been teaching Elixir and Phoenix development for years and is well known within the Elixir ecosystem for his practical teaching style and focus on real-world application development.
Final Thoughts
Build It With Phoenix by Geoffrey Lessel is one of the more practical Phoenix development courses available for developers who want to move beyond beginner demos and understand how real-time applications are actually built.
By focusing on a complete Slack-style application, the course provides hands-on experience with:
- Phoenix LiveView
- Presence systems
- Channels
- PubSub
- Ecto
- PostgreSQL
- authentication workflows
- scalable real-time architecture
For developers serious about improving their Elixir and Phoenix skills through project-based learning, this course offers a much more realistic and implementation-focused experience than most introductory tutorials.
Get Build It With Phoenix by Geoffrey Lessel today.
